In 1909, John E. Green founded a plumbing and heating business with $20 in cash in Highland Park, Michigan. John E. Green's sons built upon what their father started and rapidly expanded the business in the industrial and institutional fields, laying the groundwork for what the company is today - one of the largest and most diversified mechanical contractors in the country.John E. Green Company (JEG) is a national leader in the fabrication and installation of plumbing, HVAC, process piping, and fire protection systems. We also specialize in design build solutions and 24/7 emergency service.JEG prides itself on being one of the country's mechanical contractors with ISO 9001 & ISO 14001 certifications. We typically employ over 600 team members, as well as 500-900 skilled tradespeople. We work as a union contractor throughout the country and maintain offices in Michigan and Tennessee.JEG is recognized by Engineering News Record as one of the largest specialty contractors in the United States.